standard register names (accumulators)
ax (accumulator, 16 bit?)
al is the lower 8 bit part of ax
ah is the higher 8 bit part of ax
eax (Extended accumulator. 32 bit?)
rax (64 bit accumulator)
mov eax, 1 (move the value 1 into the register eax
register names for bases + bx (16 bit) * bl * bh + ebx (32 bit)
count register + cx (16 bit) * cl * ch + ecx (32 bit)
data registers + dx (16 bit) * dl * dh + edx (32 bit)